Optimized preparation for bimodal porous carbon from lentil processing waste by microwave-assisted K2CO3 activation: Spectroscopic characterization and dye decolorization activity

This paper describes lab-scale experiments for producing optimal activated carbon (LWAC) with bimodal porous (mixed micro-mesoporous) texture under optimized conditions from lentil processing waste (LW) by microwave-assisted K2CO3 activation. The influences of various operating parameters were evaluated including impregnation ratio (IR), carbonization temperature (CT) and carbonization time (Ct). The BET surface area (S-BET) and total pore volume (VT) were chosen as main criteria in optimization. The optimized parameters were IR ratio of 3:1, CT of 800 degrees C and Ct of 1 h. The physicochemical properties of LW and LWAC were identified with diverse analytical techniques. LWAC possessed high S-BET of 1875 m(2)/g and large V-T of 0.995 cm(3)/g. The LWAC was then tested for its feasibility as cationic (Methylene blue (MB)) and anionic (Methyl orange (MO)) dyes adsorbent. It was found that LWAC has an adsorption capacity of 625 mg/g for MB and 476 mg/g for MO at 30 degrees C. (C) 2019 Elsevier Ltd. All rights reserved.